Патент USA US2029317
код для вставки‘ Feb. 4, 1936. J. A. GUYER El‘ AL - 2,029,317 ‘GAS MAKING APPARATUS Filed March '19, 1952 4% Y oz T _ , A/yrlacéoh I‘nlet '1 @1-3'9‘ CFrSoetkialms .Secfzbn 0 B/éTAkueiaZtrs 9999 O Q Q @000 0 O 00 » V 2 Sheets-Sheet 1 2,029,317 Patented Feb. 4, 1936 U ITED STATES PATENT GFFIQE 2,029,317 GAS MAKING APPARATUS Jesse A. Guyer, Frederick E. Frey, and Walter F. Huppke, Bartlesville, Okla, assignors to Phil lips Petroleum Company, Bartlesville, 0kla., a corporation of Delaware Application March 19, 1932, Serial No. 600,017 2 Claims. This invention relates to an apparatus to be used with a process for the catalytic conversion of hydrocarbon fluids into fuel gas by reacting a hydrocarbon with steam in the presence of a cata U lyst at elevated temperatures. A normal city gas plant in order to care for the peak load demand would have to be designed to carry a larger amount of gas than would be necessary for the ordinary demand. By employ 1 (l ing this process in conjunction with a city gas plant, it is not necessary to design the regular plant to care for the peak load demand. A small er out?t running economically at full rated ca pacity throughout the day will care for the or dinary load; any greater demand on the system can easily be cared for by the catalytic conversion of hydrocarbon gases. These gases may be stored as liquids under a very small pressure, thereby insuring the city plant against contingencies. It is therefore an object of this invention to provide an improved apparatus for the conm'ier cially practical manufacture of fuel gas from hy drocarbon fluids. A further object of the invention is to furnish 25 an apparatus to manufacture a fuel gas by pass ing a limited amount of steam, together with a hydrocarbon ?uid through a catalytic chamber or chambers of restricted volume. Another object ofv this invention is to supply 30 equipment to control all conditions under which this reaction is conducted, whereby it is possible to produce a gas having predetermined charac teristics of thermal value and density. (01. 48--94) cases, temperatures higher than are necessary to obtain the catalytic reaction are used to pro duce a gas substantially free from hydrocarbons. We have found that if, in the manufacture of fuel gas, higher ?ow rates and lower steam ratios than hitherto used are employed, then well known catalysts of the Fe group activated with di?icultly reducible oxides of Al, Cr, V, etc., can be used to commercial and practical advantages. The proc ess may be applied more advantageously to the higher hydrocarbons of the paraffin type such as propane and butane, but gases containing a large proportion of the comparatively unreactive meth ane, as well as gases produced by cracking, which contain the simpler ole?nes, may be treated suc 15 cessfully by the process. We can also use liquid hydrocarbons which can be completely vaporized. Under conditions Where speci?c proportions of hydrocarbons are reacted with speci?c propor tions of steam at an elevated temperature pref 20 erably above 600° C. in the presence of certain catalysts, the operation can be so controlled that portions of the hydrocarbons remain unreacted so that fuel gas of a desired thermal value and density can be produced. The complete conversion of hydrocarbons into oxides of carbon and hydrogen yields a gas with a calori?c value of no more than 325 B. t. u. per cubic foot. Since a calori?c value in excess of 500 B. t. u. per cubic foot is usually desired in 30 a fuel gas it is desirable that some of the hydro carbons pass through the catalytic chamber or chambers without conversion into water gas. In A still further object is to provide an appa ratus to react steam, in such a proportion to the hydrocarbon gas as to produce substantially no the past, such catalysts as nickel, iron, and cobalt have been employed in the conversion of hydro carbonization, thereby eliminating the difficulties of pipes clogging and inactivity of the catalysts. ing gas of lower calori?c value. When employed in this manner, carbon deposits are formed. Carbon formations can be tolerated in known methods in which a catalyst is supported on heat storing material disposed in a chamber into which heating gases and reactants are alternately intro duced for alternate heating and gas making cycles, since restricted passages, subject to stop page by carbon, are unnecessary. But in meth ods of this type, wide variations in temperatures during the gas making cycle are unavoidable and great fluctuations in the properties of the gas Another object is to provide an apparatus of 4 0 this kind, having a number of catalyst chambers arranged in parallel relation, through which the mixture of steam and hydrocarbons ?ows, the catalyst being exposed in units su?iciently ex tended to permit the introduction of the heat re 45 quired by the reaction through the con?ning wall adjacent to the catalytic body. A further object of the invention is to provide an apparatus by which the process may be carried out in a practical manner. Water gas, composed of oxides of carbon and hydrogen, is commonly prepared in a state of comparative purity for use in catalytic synthesis by the interaction of hydrocarbons with steam in the presence of a suitable catalyst. A large ex 55 cess of steam, moderate flow rate, and, in most carbons, without steam, into hydrogen-contain produced take place unless complete destruction of the hydrocarbons is intended. For producing a gas of uniform properties, a continuous proc ess is desirable, but neither can partial combus tion be used to avoid carbon, nor complete con version into water gas be used economically, to produce a gas. having a low speci?c gravity and. 2,029,317‘ 2 at the same time an adjustable calori?c value in the desired range. In the case where a gas of higher calori?c value is desired, then certain portions of the hydrocar bons must remain unreacted. In order to control these conditions, restricted passages and cata lytic chambers of restricted volume must be em ployed.» Carbon deposits formed would tend to clog these passages and inactivate the catalysts. We have found that by introducing limited amounts of steam into the reaction, the forma tion of carbon may be prevented, even while some of the hydrocarbons still escape the water gas conversion. This will continuously produce gases 15 of desired predetermined calori?c value. The amount of steam may vary depending on the properties of resulting gas desired. Less than one. atom of oxygen in the form of water for each atom of carbon in the hydrocarbon may ‘be used 20 and still prevent the formation of carbon de posits. ' With the foregoing objects outlined and with other objects in view which will appear as the de scription proceeds, the invention consists in the 25 novel features hereinafter described in detail, illustrated in the accompanying drawings, and more particularly pointed out in the appended claims. In the accompanying drawings, Fig. 1 is a vertical section, partly in elevation and more or less diagrammatical, of an appa ratus for carrying out the process. ‘2 is ‘a ‘horizontal'section of Fig. 1, taken _ on the line 2-—-2. Fig. 3 is a view similar to Fig. 2, but illustrating an alternative method of installing the catalyst. The apparatus preferably comprises a housing 3 of heat insulating material divided by a baffle plate 9a of similar material, into upper and lower 40 chambers ‘which are in communication with one If air is to be mixed with the hydrocarbon ?uid before the latter is introduced into the preheater A, said air may be introduced through a valved branch F of the inlet pipe I4. At the point A’, the preheated hydrocarbon ?uid, with or Without admixture of air, is ad mixed with the steam from the super-heater 8. If too much steam for reaction with the hy drocarbons is produced by the waste heat, some of the steam may be discharged through a valved pipe 12a, or if desired, for reducing the amount of heat imparted to the boiler, some of the hot v?nished gas, instead of passing directly through the boiler I I, may be by-passed through a valved passageway N before it is introduced into the 15 pipe G. For the purpose of diluting the ?nished gas with flue gas, a valved pipe I‘! connects the ?ue H] with the pipe G, and a pump Ila is interposed in this conduit for forcing the ?ue gas into the 20 pipe G. Another valved pipe 16 is connectedto the pipe G for use in introducing an enriching ?uid, such as hydrocarbons, into the ?nished gas line. A valved conduit i5 leads into the manifold D 25 between the catalyst tubes and the chamber D’ for the purpose of introducing a hydrocarbon en riching ?uid into the hot fuel gas before the latter is cooled by imparting some of its heat to the boiler H. In this way, the enriching ?uid may 30 be cracked somewhat by the heat of the hot fuel gas leaving the catalyst tubes. 'The catalyst in the tubes C’, C2, C3 and C4 preferably consists of wire screens of any suit able cross section. For instance, each screen may 35 be of substantially the same length as the tube within which it is placed, and may be M-shaped in cross section. Such screens may be of nickel, made active by oxidizing and then reducing to produce a roughened condition. Afterwards, the 40 another at ‘one end only of the housing. At the screen is coated with a solution of a nickel and opposite 'end of the housing, a suitable burner 4 aluminum nitrates, which, when dried and heated, extends into the lower chamber. That chamber results in the formation of a catalytic nickel pro is divided into upper and lower compartments by moted by alumina upon subsequent treatment with a-heated hydrocarbon atmosphere. 45 a horizontal plate 4a of heat conducting material. Thecompartment below the baffle 4a is the com In starting the process, the boiler H may be bustion chamber of the apparatus, and it is pro heated by a burner H, and at such, time as it is vided at one end with a perforated wall "6 through desirable to pass the combustion gases fromcham whichgases of combustion travel to a passageway ber D’ into the stack H], such chamber is connect 50 ‘I, that conducts the same into the upper cham I ed by a passageway M with such stack, suitable ber ‘of the apparatus. In the latter chamber, a dampers G’ and G2 being arranged respectively . steam preheater or super-heater 8, and an air in the pipe G and in the passagewayM. preheater 9, are positioned in serial arrangement. Instead of employing catalyst tubes of the type After'the combustion gases pass through the up shown in Figs. 1 and 2, we can use a single tube 55 per chamber, they are discharged through the with catalytic ‘chambers interposed therein in ?ue or stack I0. spaced relation, as shown in Fig. 3. In this ar The air preheated in 9 is fed by a conduit 9b rangement, the single tube will be positioned be into the combustion chamber. low the baffle 9a, and at substantially the same A waste heat boiler ll, positioned at one end elevation as the catalytic tubes in Figs. 1 and 2. to of the housing, is ‘provided with an outlet conduit Referring to Fig. 3, it will be noted that the hy drocarbon ?uid introduced through the pipe i4 l2 having a control valve E. This conduit dis charges steam into the preheater or super may be mixed with (air from the branch F before entering the preheater A. As in Figs. 1 and 2, heater 8. steam from the preheater 8 is mixed with the The hydrocarbon ?uid to be treated is intro 65 duced through a conduit I4, connected to a pre hydrocarbons or hydrocarbons and air at the heater A, arranged in the passageway l and dis point A’, and thenthe mixture enters the cata charging 'at A’ into a manifold B. This manifold, lyst tube 0. This tube is made up of a number as ‘best shown in Fig. 2, communicates with a of cross pipes B’, B2, B3, B13, B5, which lead to series of catalyst tubes C’, C2, C3, C4 that extend and from catalyst chambers C’, C2,'C3, C4, C5, beneath the ba?ie 9a and above the plate 4a. and C6. Each of these-chambers preferably con tains a-catalyst composed of metals of the iron A manifold D receives the gases from the cata lyst tubes and conducts the same through conduit group activated with dif?culty reducible metal E’ into a chamber D’ in which the waste heat lic oxides. For example, it may be nickel acti boiler H is ‘arranged. ' 60 ' 65 ‘T on The fuel gas or ?nished I vated with an alumina. gas is ‘discharged through a-‘pipe 'G. The ‘catalyst may-also be of pumice or porce 75 3.. 2,029,317‘ lain crushed and screened from 3 to 6 mesh to the inch size, and impregnated with nickel and aluminum nitrates which are decomposed by cal cination at low red heat to give the oxides. For (If the purpose of holding such a catalyst in position, a perforated alloy plate is spot welded into place at one end of the chamber. Afterwards, the cata lyst is put in and held in place by a second per forated alloy plate. 10 In order that the catalyst chambers may be accessible, openings are placed in the opposite walls of the housing 3 where the catalyst cham bers are located, and these openings are normally closed by any suitable doors 25. As in Figs. 1 and 2, the fuel gas leaving the last one of the catalyst chambers CS, enters a pipe D which conducts the same to the boiler l I, (Fig. 1). If desired, hydrocarbon ?uid, with or without admixture with air, can be fed by way of pipes J 20 and valved branch pipes J ’, J2, J3, J4 and J5, into the inlet ends of the catalyst chambers. If the catalyst sections are arranged along the walls of the housing, the small pipes J’, J 2, J 3, J 4 and J5 for the addition of hydrocarbons progres sively in small portions, may be run through the furnace in such a way that they would not be exposed to excessive temperatures so that undue cracking is prevented. In putting the apparatus in operation, steam is ?rst generated by heating boiler II by the com bustion of fuel gas in the chamber D’. Air for combustion here is admitted through gate con trolled opening K, and the products of combus tion are allowed to pass through the boiler tubes and into the stack l0 through opening M, while the valved pipe G remains closed to prevent the passage of combustion gases into the fuel gas exit. When the catalyst tubes have been heated somewhat by firing combustion chamber 5, steam is admitted to said tubes by opening valve E, ?r ing through burner H is discontinued, gate K and damper G2 are closed, and, when the oper ating temperature is approached, hydrocarbon ~ ?uid is admitted through inlet 14. The ?nished gas is allowed to pass out through pipe G. In the operation of the apparatus as described, the incoming gases to be treated, such as propane or butane, or mixtures of these, enter through pipe M in liquid or gaseous form. Ordinarily, they will pass through heater A where they will be heated by the combustion gases. , After being heated by the heat exchanger A, the hydrocarbons pass by point A’, where the gases are mixed with a controlled quantity of steam. This mixture is led into catalytic tubes or chambers. The reaction is extremely endothermic, re quiring the addition of large quantities of heat to the reaction chambers. Since the reaction is strongly endothermic, the heat withdrawn at the catalyst lowers the temperature to such a degree that the reaction ceases when conversion is only partly complete. This can be prevented by intro (55 ducing additional heat into the catalyst or by preheating the gases to an impractically high temperature. We have discovered that the use of excessive preheat temperatures can also be avoided by a method for which the catalyst tube shown in Fig. 3 is used. The gaseous mixture, to undergo conversion, is heated above minimum re action temperature to only a fraction of the ex~ tent necessary to subsequently cause complete reaction, after which on passing through a por tion of the catalyst bed, a partial reaction takes place, the temperature falling to a minimum re action temperature. The gas mixture, after un dergoing partial conversion in this manner, must be heated to undergo a further partial conver sion. Additional partial conversions may be sub sequently applied until the desired reduction in calori?c value is obtained. The process in the apparatus may be conducted at about 650° to 800° C., but best results are ob tained in most cases within a range of 700°~750° 10 C. We have found such temperatures can be maintained easily if the catalyst is divided into several portions which are so arranged that the reacting gases pass through them in parallel re lation or successively. The catalyst segments in 15 Fig. 3 are connected in the furnace by a piece of tubing of sufficient length so that the heat to be used in the reaction is taken up by radiation and conduction from the furnace. By regulating the furnace temperature, the heat loss due to the 20 endothermic nature of the reaction may be com pensated by the connecting tubes, and the tem perature of all the catalyst bodies kept high enough to permit reaction. After the mixture has reacted to the desired degree in the catalytic chambers, it passes out through pipe E’ to heat exchanger ! l to heat the incoming water and from there the reacted gas passes through pipe G where it may be diluted by ?ue gases. If desired, it may be diluted by 30 air, combustion products, or other diluent gases, or enriched with hydrocarbons, depending on the calori?c value and density desired. The ?nished product leaves pipe G to the necessary source for use as fuel gas. It may be desired to divert the hydrocarbons directly into the catalytic chambers. In this event, the valves in branch pipes J’, J2, J 3, J 4 and J 5, (Fig. 3), are partially opened, and the hydro carbons pass directly into the catalytic cham 40 bers. This will avoid excessive cracking prior to catalytic conversion when the more unstable hydrocarbons are treated. Air may be intro duced to supply heat to the several catalyst chambers alone or in admixture with hydrocar 45 bons. The combustion gases, assisted by radiation from ba?ie 4a, function to maintain the tempera ture of the reacting mixture ?owing through the catalytic chambers, and from there pass up into 50 the stack In. As example of the application of the process to be conducted in the apparatus, the following data are cited. In practicing the invention, an apparatus essentially of the type shown in Figs. 1 and 2 was used. The catalyst consisted of 150 square feet of nickel screen in strips 12 feet long and 16 inches wide, folded longitudinally to per mit their introduction into chromium alloy steel tubes C’, C2, C3, C4 of about 31/2 inches in in 60 ternal diameter. The tubes were disposed in the furnace which maintained in the tubes the average temperature shown in the following table in the neighborhood of the catalyst. A mixture of steam and butane was passed at a uniform 65 rate through the tubes wherein conversion into gas of lower speci?c gravity and calori?c value was produced. The catalyst screen was activat ed before practicing the process by heating the screen three hours in air at 800° C. The oxi dized surface was then reduced to a rough but tenacious coating by reducing with hydrogen at 400° C., after which a strong aqueous solution of nickel and aluminum nitrates in the molecular ratio of 1 to 2 was applied. A clean gas, free 4 2,029,317, from tar, was produced continuously over a long period without the formation of carbon. The following shows the results: What we claim and desire to secure by Letters Patent is: 1. Gas generating apparatus particularly adapted for use in connection with highly en Temperature degrees centigrade _______ _. Butane-pubic feet per hour _____ _. Steam-pounds per hour ________ __ Finished gas-cubic feet per hour Finished gas—speci?c gravity____. Finished gas B. t. u. per cubic foot Finished gas analysis: 10' Carbon dioxide ____________________ “ Carbon monoxide _____ __ dothermic catalytic gas producingrreactions, said apparatus comprising a combustion chamber, a radiant heating chamber adjacent to but sepa rated from said combustion chamber, a reaction tube extending through said radiant heating chamber, said tube comprising spaced catalyst containing chambers and intermediate connect ing conduits, said conduits being of such length as to enable the reaction mixture passing there through between catalyst chambers to ‘absorb Propane _______ __ Both increased ?ow rate and decreased cata lyst temperature decrease the extent of con version to give a resultant increase in calori?c 20 value. The properties of the gas may also be modi?ed by the admixing of other gases. In case it is desired to decrease the calori?c value and increase the speci?c gravity of the .25 30 gas, air, combustion gases, or other suitable suf?cient heat from said radiant heating cham ber to enable the reaction to proceed, in part at least, in said chambers, whereby excessive pre heat temperatures of said reaction mixture may be avoided, and additional means for selectively controlling the temperature of said mixture in said conduits. 2. Gas ' generating apparatus particularly adapted for use in connection with the endo thermic generation of gas, said apparatus com diluent gases can be added after the gases come prising a source of heat, a reaction tube in in out of the reaction chamber. In case it is de sired to have a gas of very high calori?c value and comparatively 10W gravity, hydrocarbon can be added through H5 to the ?nished gas after direct heat exchange relationship with said source of heat, said tube comprising a plurality of spaced reaction chambers and intermediate connecting portions, whereby the reaction mixture is adapt ed to pass through said chambers in succession, 30 said connecting portions being of such length as to enable the reaction mixture passing there through to absorb su?icient heat from said heat source to enable the gas generation to proceed, in part at least, in said reaction chambers, and 35 means for introducing hydrocarbons and the like into said mixture progressively as it passes through the apparatus. JESSE A. GUYER. it leaves the reaction chamber. Simpler paraf ?ns may also be added through 95 to the hot gas leaving the catalyst. This would e?ect consid erable cracking of the hydrocarbon, and also a large increase in volume. 35 From the foregoing it is believed that the con struction, operation and advantages of our im proved apparatus may be readily understood by those skilled in the art, and it is apparent that changes may be made in the details disclosed, without departing from the spirit of the inven tion, as expressed in the claims. FREDERICK E. FREY. WALTER F. HUPPKE. 25
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